Method of producing molybdenum-bearing iron



Patented May 10, 1932 v No Drawing.

5 xrssocn orrennsr HILLS, new YORK METHOD or rnonucrne MQ YBDENUM- BEARI'NGmen Y ,5

Application filed November The invention relates to a novel and useful method of producing molybdenum-bearing pig iron, and therefrom lybdenum alloy grey, white, 5 semi-steel castings.

The objects and tion producing momalleable and advantages of my invenare stated hereinafterin part and in part Will become obvious h'erefromto those skilled in the art, or may be ascertained through practicing the invention.

The invention consists in the novel steps, sequence of steps, processes andprocedures hereinafter disclosed full and-exemplified by a description of the present preferred practice thereof. p v The invention is directed primarily to pro ducing .a molybdenum-bearing pig iron, and usually the product will be a low-percentage 39 iron.

of low grademolybdenum-bearing' plg Such a'molybdenum-bearing pig iron has inherent properties and advantages of great direct value in the arts. not of my process,

, ingly efficient and 2 able for use in making the so-called hot-metal T his prodsatisfactory material suitalloy iron :additions'in the manufacture of molybdenum steel. V p I Another very important use and availability of this molybdenum-bearing pig iron 39 of my invention is in the of producing grey, white, semi-steel castings from metal melted in the cupola furnace.

. Referring now in 35 ferred manner of practicing my process, and having in view primarily the molybdenum-bearing pig iron,

further process malleable and detail to the presentprothe production 'of I use i a proportional quantity of a molybdenum com pound as an ingredient of the blast furnace charge to give the lybdenum in the desired percentage of mopig iron, and sub ect 1t wlth the remainder of the charge to the smelting operation, whereby practically the entire moly 45 duced as an alloy into the pig iron.

bdenum content of the charge is intro- Various molybdenum compounds may be employed in my process, venient or desirable, such ide,

as may be found conas molybdenum oxcalcium molybdate, or molybdenum sul- If desired, there may be addedto an for example, is an exceed- 1, 1927. Serial No. 230,381.

ordinary blast furnace charge sufficient of the molybdenum compound of known metallic contentto secure the desired orpredetermine percentage of molybdenum inthe p'ig iron, as for example, to introduce four pounds of molybdenum for every one hundred pounds of iron contained in thechar-gel In view of the continuous operation and periodic charging the blast furnace with predetermined quantities of the charging mate-F rials, the'molybdenum bearing compound, in predetermined amount, may be included -vmws ws P ",OFFW SJv 1 With any one of the charging materials. The

iercentage of molybdenum obtained in the pig iron will be found practically equivalent .to the predetermined percentage introduced intothe furnace charge. i

The molybdenunrcontaining compound introducedinto'the blast furnace charge'in the manner described or any other suitable manr ner during the operation goes down through the furnace with the other ingredientsof the chargeand is progressively subjected tothe smelting or reducing operation of the furfnace. As the surface operation proceeds and the charge materials are subjected to the gradually increasing temperatures and progress to a state of complete fusibility, the mo lybdenum is released from its compound and tures prevailing in the blast furnace. In any 1 molybdenumfor oxygen, and

and progres- -downwardly 1 event, substantially the entire molybdenum content 'of' the molybdenum bearing compound introduced into the charge Will be transmitted'asan alloy'into the pig iron.

The low percentage molybdenum pigiron the pig iron of my invention may be run in the molten state from the blast furnace and be mixed with the molten metal in the steel 7 making furnace to produce a steel containing thedesired or predetermined percentage of molybdenum alloy. This iron also provides ajmolybdenum alloying agent whichcontains a very low percentage of impurities and which requires no reducing action to effect the desired percentage alloy.

7 The molybdenum pig iron of my invention likewise provides a most excellent and suitable material for addition to the charge of the cupola furnace to produce a desired molybdenum alloy for casting. It may be introduced as apart of the original charge of the cupola furnace in such relative proportion as to effect the desiredpercentage alloy of molybdenum inthe product from the cupola furnace. It insures uniform distribution of the alloy throughout the product and without the introduction of any harmful impurities whereby castings made from such alloy iron are of very superior quality and purity. Should it be desired, the molybdenum pig iron may be melted in a separate cupola, and the molten molybdenum-bearing pig] iron therefrom be added in desired proportion to the output of a cupola which is meltingordinary iron to effect the desired alloy.

.Alloy additions to iron, produced from cupola melting are sometimes made in the cupola ladle before pouring the castings. This practice is not productive of the best or most uniform results and this is especially the case with high-temperature melting metals, such as molybdenum, or ferroanolybdenum. Molybdenum-bearing pig iron has a relatively, low melting temperature and by adding it to the usual charge of the cupola furnace, a uniform distribution of this alloying agent insures uniform distribution of the alloy throughout the molten iron, and without the introduction of any harmful impurities, there results a superior molybdenum' alloy iron for casting.

It will be understood that variationsmay be made from the details of my-process as herein exemplarily disclosed without departing from the principles of the invention and.

without sacrificing the chief advantages thereof. It will be understood also that the ient term to designate the product of a blast furnace irrespective of Whetherit is molten 1. The process of producing molybdenum.

containing cast iron which comprises melting together iron and a molybdenum bearing alloy having a melting point so that it will melt at substantially the same time as the iron and a molybdenum content such that the desired percentage of molybdenum is substantially uniformly distributed throughout the cast product. p a

2. The process of producing molybdenum containing cast iron which comprises melting together iron and a molybdenum bearing cast iron, the molybdenum content of which is such that it has a melting point whereby it Will melt at the same time as the iron and the cast product will contain the desired percentage of molybdenum.

3. The process of producing molybdenum containing cast iron which comprises. melting iron and an iron having a molybdenum content such that their melting points are .relatively close and causingthem to intermix in the molten state that the resultant castings will contain the desire denum. V

4. The process of producing molybdenum containing cast iron which comprises melting non-molybdenum bearing iron and separately melting a molybdenum bearing cast iron and mixing the two molten substances in such proportions that the resultant castings will contain the desired percentage of molybdenum.

5. The process of producing molybdenum containing cast iron Which comprises melting non-molybdenum bearing iron'and separately melting a casting iron having a relatively ALAN KISSOCK. I,

term pig iron is used herein as a conven- 

